Designed rationally with lubricating grease used in the advanced sliding bearings of the pulleys, the machinery occupies a certain position in the early history of machinery in China.

 
  • 它们年代久远,结构设计成熟,其中滑车采用了先进的滑动轴承结构和润滑剂,在中国早期机械史上占有一定的地位。
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